The present invention relates to a microwave oven, and more particularly, to an exhaust airflow passage structure of a ventilation-hooded microwave oven for discharging a hot air stream generated from an oven range that is installed below the microwave oven.
In general, a ventilation-hooded microwave oven is installed above an oven range and has an exhausting function for discharging hot air, smoke, etc. generated from the oven range in addition to a cooking function, i.e., an original function of a microwave oven.
Referring first to FIGS. 1 to 3, a conventional exhaust airflow passage structure of the ventilation-hooded microwave oven will be explained. FIG. 1 shows a general arrangement of the oven range and the ventilation-hooded microwave oven. That is, hot air, smoke, etc., which are generated from the oven range 2 during its use, flow toward the ventilation-hooded microwave oven 4 (so-called OTR (Over The Range), hereinafter referred to as xe2x80x9cmicrowave ovenxe2x80x9d) installed above the oven range, and are discharged upward through the exhaust airflow passage of the microwave oven 4.
FIG. 2 is a front sectional view showing a structure of the exhaust airflow passage, and FIG. 3 is a right-side sectional view showing the exhaust airflow passage. As shown in FIGS. 2 and 3, a cavity 14 in which foodstuffs are cooked is provided within an outer case 12 for defining an external appearance of the microwave oven. A predetermined space for forming a passage through which air flows is provided between a left side 14a of the cavity 14 (with respect to the direction of the figures) and the outer case 12.
A base plate 16 defines a lower surface of the microwave oven 4, i.e., a surface opposite to the oven range 2, and a suction portion 16a for sucking up the hot air and the smoke generated from the oven range 2 is also formed in the base plate 16.
Beside the cavity 14 is provided an electric equipment installation chamber 20 in which several electric equipments for generating microwave to be introduced into the cavity 14 are installed. A bottom plate 18 is formed on a bottom surface of the electric equipment installation chamber 20, and a passage hole 22, through which air flows via the electric equipment installation chamber 20, is formed in the bottom plate 18. Further, an exhaust motor 24 for providing driving force for discharging the hot air and the smoke generated from the oven range 2 is installed on a rear and upper portion of the cavity 14. The exhaust motor 24 is connected to an additional exhaust duct and is communicated with a front or rear exhaust grille of the microwave oven 4. Thus, the hot air and the smoke can be discharged therethrough.
In the prior art constructed as such, the exhaust motor 24 is operated so as to discharge the hot air or smoke generated from the oven range 2. The hot air and the smoke are sucked through the suction portion 16a of the base plate 16 by means of suction force of the exhaust motor 24, and then they flow and are discharged in the direction of arrows shown in FIGS. 2 and 3.
That is, the hot air and the smoke passing through the base plate 16 are divided into two air streams with respect to the cavity 14. Then, one of the two streams flows between the outer case 12 and the left side of the cavity 14 and toward the exhaust motor 24 located above the cavity 14, while the other stream flows toward the exhaust motor 24 through the passage hole 22 perforated in the bottom plate 18 and via the electric equipment installation chamber 20.
However, there are the following problems in the conventional exhaust airflow structure that works as described above.
That is, in the electric equipment installation chamber 20 are provided major electric equipments including a magnetron as a part for oscillating microwave in order to heat and cook the foodstuffs in the cavity 14, a high-voltage transformer for applying high voltage to the magnetron, etc. Moreover, since the contaminated air, which is generated when the foodstuffs are cooked in the oven range, is sucked through the suction portion 16a of the base plate 16 of the microwave oven 4, the magnetron and the high-voltage transformer are contaminated by the air passing through the electric equipment installation chamber 20. As a result, there are problems in that the operation reliability of the magnetron, the transformer, etc. is lowered and the performance of the microwave oven is deteriorated.
Furthermore, if the airflow passage for a hood function is formed in the electric equipment installation chamber 20 similarly to the prior art, the volume of the electric equipment installation chamber 20 is increased in proportion to that of the passage. Thus, there is also a problem in that the size of the microwave oven as a whole is increased.
It is an object of the present invention to prevent electric equipments installed within an electric equipment installation chamber from being contaminated, by constructing a hooded microwave oven so that air sucked through a base plate thereof cannot enter the electric equipment installation chamber.
It is another object of the present invention to provide a compact ventilation-hooded microwave oven in which width of an electric equipment installation chamber can be minimized by not making an airflow passage going by way of the electric equipment installation chamber disposed on a right side of the ventilation-hooded microwave oven.
According to an aspect of the present invention for achieving the above objects, a hood apparatus of a ventilation-hooded microwave oven, in which a cavity defining a cooking space and an electric equipment installation chamber for accommodating electric equipments to generate microwave required for the cooking are provided within an outer case, comprises an exhaust motor for providing driving force for sucking up contaminated air below the ventilation-hooded microwave oven; a suction portion through which the contaminated air enters the ventilation-hooded microwave oven by means of the suction force of the exhaust motor; and an exhaust airflow passage formed in a space between the cavity and the outer case, so that the air sucked through the suction portion can flow toward the exhaust motor.
The suction portion is formed in a base plate for defining a bottom surface of the outer case.
Further, communication between the suction portion and the electric equipment installation chamber is prevented by a bottom plate for defining a bottom of the electric equipment installation chamber.
The exhaust airflow passage is formed so that the sucked air can flow from a bottom to a top of the ventilation-hooded microwave oven via a gap between the outer case and the cavity opposite to the electric equipment installation chamber.
According to the present invention, contamination of the electric equipments within the electric equipment installation chamber is prevented because the exhaust airflow passage for performing a hood function is formed so as not to pass through the electric equipment installation chamber.